New Zealand First leader Winston Peters insists that there is a "massive" difference between his party getting funding from corporate donors via secret trusts and other parties getting it.
He won't say what, but is promising to spell it out in Parliament today.
But he failed in Parliament yesterday to give answers about Sir Robert Jones' $25,000 donation to the secret Spencer Trust in 2005, despite having promised during the weekend that he would.
Sir Robert yesterday would not rule out calling in the police if he did not get a satisfactory response about what happened to his money.
Outside the House, Mr Peters was asked what the difference was between his party getting large donations from corporate donors via secret trusts and other parties getting it.
Mr Peters said the difference was "massive", but that the reporters were not capable of understanding it. He said he would explain it today.
Mr Peters, his lawyer Brian Henry and his chief of staff, Damian Edwards held a 45-minute meeting yesterday with Prime Minister Helen Clark and her chief of staff Heather Simpson.
Mr Peters, who is Foreign Minister, again assured her that there had been no illegality and she said she accepted his word.
She told Parliament she had not expected Mr Peters to answer questions about the Spencer Trust, any more than she expected National leader John Key to raise questions about the Waitemata Trust - a trust that has given National more than $2 million since 2001.
National has declared the Waitemata Trust donations.
Mr Peters has referred questions about the Spencer Trust to his brother Wayne Peters, who won't give any details about it.
Sir Robert has sought assurances that the $25,000 he gave for New Zealand First's 2005 campaign through the Spencer Trust made it to the party.
Sir Robert said he was prepared to probe other donations made previously to Mr Peters.
"Honestly, these are police matters of course," he said yesterday.
He was waiting for a response from NZ First to a letter he wrote last week to MP and former party president Dail Jones, asking about the donation.
Sir Robert said he had given Mr Peters another $150,000 - $50,000 when he started New Zealand First, $50,000 towards his Winebox legal costs and $50,000 in the mid-1990s.
Sir Robert said while he was not yet looking at the other $150,000, he was prepared to "delve" if Mr Peters was to attack him.
"If he wants to take me on, I'm not bragging about this, but I certainly won't tolerate lies and deceit being told about me," he said.
New Zealand First has not declared any donations since he donated.
The money could have been lawfully laundered from the Spencer Trust to other legal entities and to the party in smaller amounts.
Party president George Groombridge says he has never heard of the Spencer Trust. The Electoral Commission noted that the statute of limitations had expired for prosecution of electoral law offences related to donations returns for 2005.